... Spectrum of the- second product showed two bands at 1683 and 1598 cm—1 in the carbonyl region and the NMR spectrum showed peaks at 5 2.20 (5, 61-1), 8.05 (double (1, 2H), 3.90 (double d, 2H), 6.04 (s, 1H, 1) Part VI: H. Ohtsuka, T. Miyasaka, and K. Arakawa; Chem. ...